1. On September 15, 1821, New Mexico officially became a territory of Mexico. New Mexicans celebrated their independence from Spanish colonial rule and enjoyed a brief period of autonomy before the American invasion in 1846.

2. In 1910, the Brotherhood of the Mexican Railway Carmen was founded in El Paso, Texas, to represent Mexican-American railroad workers in the Southwest. Though based in Texas, the union's jurisdiction extended into New Mexico and helped improve working conditions for thousands of laborers.

3. On September 15, 1924, the Navajo Tribal Council was established as the governing body of the Navajo Nation. The council played a key role in preserving Navajo culture and tradition while also advocating for greater political and economic rights for its people.

4. In 1957, the University of New Mexico's Institute of Meteoritics was established to study meteorites, comets, and other extraterrestrial objects. Over the years, the institute has made numerous discoveries and contributed to our understanding of the origins of the solar system.

5. On September 15, 1969, the Zuni Tribe of New Mexico filed a land claim against the federal government, seeking compensation for tribal lands that had been taken without consent. This and other lawsuits led to the landmark Indian Claims Commission Act of 1978, which helped address centuries of injustice and dispossession suffered by Native American tribes across the country.